[in-ter-feer-uh ns]
See more synonyms for interference on
  1. an act, fact, or instance of interfering.
  2. something that interferes.
  3. Physics. the process in which two or more light, sound, or electromagnetic waves of the same frequency combine to reinforce or cancel each other, the amplitude of the resulting wave being equal to the sum of the amplitudes of the combining waves.
  4. Radio.
    1. a jumbling of radio signals, caused by the reception of undesired ones.
    2. the signals or device producing the incoherence.
  5. Football.
    1. the act of a teammate or of teammates running ahead of a ball-carrier and blocking prospective tacklers out of the way: to run interference for the halfback.
    2. such a teammate or such teammates collectively: to follow one's interference.
    3. the act of illegally hindering an opponent from catching a forward pass or a kick.
  6. Aeronautics. the situation that arises when the aerodynamic influence of one surface of an aircraft conflicts with the influence of another surface.
  7. Linguistics.
    1. (in bilingualism and foreign-language learning) the overlapping of two languages.
    2. deviation from the norm of either language in such a situation.
  8. the distorting or inhibiting effect of previously learned behavior on subsequent learning.
  9. Psychology. the forgetting of information or an event due to inability to reconcile it with conflicting information obtained subsequently.
  1. run interference, Informal. to deal with troublesome or time-consuming matters, as for a colleague or supervisor, especially to forestall problems.

Origin of interference

First recorded in 1775–85; interfere + -ence
Related formso·ver·in·ter·fer·ence, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for run interference


  1. the act or an instance of interfering
  2. physics the process in which two or more coherent waves combine to form a resultant wave in which the displacement at any point is the vector sum of the displacements of the individual waves. If the individual waves converge the resultant is a system of fringes. Two waves of equal or nearly equal intensity moving in opposite directions combine to form a standing wave
  3. Also called: radio interference any undesired signal that tends to interfere with the reception of radio waves
  4. aeronautics the effect on the flow pattern around a body of objects in the vicinity
Derived Formsinterferential (ˌɪntəfəˈrɛnʃəl), adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for run interference



1783, formed irregularly from interfere on model of difference, etc. Broadcasting and telephoning sense is from 1887. In chess from 1913; in U.S. football from 1894.

Online Etymology Dictionary, © 2010 Douglas Harper

run interference in Medicine


  1. The variation of wave amplitude that occurs when waves of the same or nearly the same frequency come together.
  2. The condition in which infection of a cell by one virus prevents superinfection by another virus.
  3. The condition in which superinfection by a second virus prevents effects that would result from infection by either virus alone, even though both viruses persist.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

run interference in Science


  1. The superposition of two or more waves propagating through a given region. Depending on how the peaks and troughs of the interacting waves coincide with each other, the resulting wave amplitude can be higher or smaller than the amplitudes of the individual waves.♦ When two waves interact so that they rise and fall together more than half the time, the amplitude of the resulting wave is greater than that of the larger wave. This is called constructive interference. ♦ When two waves interact such that they rise and fall together less than half the time, the resulting amplitude is smaller than the amplitude of the stronger wave. This interference is called destructive interference. It is possible for two waves of the same magnitude to completely cancel out in destructive interference where their sum is always zero, that is, where their peaks and troughs are perfectly opposed. See more at wave.
  2. In electronics, the distortion or interruption of one broadcast signal by others.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

run interference in Culture


The disturbance that results when two waves come together at a single point in space; the disturbance is the sum of the contribution of each wave. For example, if two crests of identical waves arrive together, the net disturbance will be twice as large as each incoming wave; if the crest of one wave arrives with the trough of another, there will be no disturbance at all.


One common example of interference is the appearance of dark bands when a light is viewed through a window screen.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Idioms and Phrases with run interference

run interference

Handle problems or help clear the way for another, as in The press secretary runs interference for the governor. This term comes from football, where it refers to the blocking of defensive players by offensive players to let the ball carrier advance. Its figurative use dates from the mid-1900s.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.